Clinical trial

Longitudinal Changes in Lower Extremity Alignment and Mechanical Axis Parameters After Bariatric Surgery in Patients With Morbid Obesity: A Prospective Observational Study

Active, not recruiting · Not applicable · 1 countries · Registry ID NCT07794566

Active, not recruitingNot applicableObservational

What this study is about

The goal of this prospective observational study is to understand whether major weight loss after bariatric surgery is associated with changes in the alignment of the lower limbs in adults with morbid obesity. The hips, knees, and ankles form a connected weight-bearing system that supports the body during standing and walking. The position of these joints in relation to one another affects how body weight and mechanical forces are transmitted through the legs. In people with severe obesity, increased body weight and changes in body shape may influence the way these forces are distributed across the lower extremities. Bariatric surgery can result in substantial weight loss. However, it is not yet fully understood whether this degree of weight reduction is accompanied by measurable changes in the alignment of the hips, knees, and ankles or in the mechanical axis of the lower limbs. This study will follow patients undergoing bariatric surgery and will evaluate them before surgery and again at approximately 3, 6, and 12 months after surgery. The study is observational. This means that researchers will observe and measure changes that occur during the patients' clinical course rather than assigning participants to a particular treatment for research purposes. The main question is whether lower-extremity alignment and mechanical-axis measurements change during the first year after bariatric surgery as patients lose weight. "Lower-extremity alignment" describes how the hip, knee, and ankle are positioned in relation to one another. The "mechanical axis" is an imaginary weight-bearing line used in orthopedics to describe how forces are transmitted through the leg from the hip toward the ankle. The position of this line in relation to the knee helps doctors understand how weight and mechanical forces are distributed across the lower limb. Researchers will examine radiographic measurements that describe the overall relationship between the hip, knee, and ankle and the contribution of the thigh bone and shin bone to lower-limb alignment. Measurements obtained before bariatric surgery will be compared with those obtained at approximately 3, 6, and 12 months after surgery. Following the same patients over several time points is important because weight loss after bariatric surgery occurs progressively rather than at a single moment. Repeated measurements will allow researchers to determine whether lower-limb alignment remains stable, changes early after surgery, changes gradually as weight decreases, or shows different patterns between individual patients. The study will also explore whether the amount and course of postoperative weight loss are related to any observed changes in lower-extremity alignment. The researchers do not assume that losing weight will automatically correct an existing bow-legged or knock-kneed appearance, or that every patient will show a measurable change in skeletal alignment. Some aspects of lower-limb alignment are determined by the shape and orientation of the bones and may remain stable. Other aspects of weight-bearing posture and the relationship between the joints may potentially change as body weight and body composition change. The purpose of this study is to objectively measure these changes rather than assume that they will occur. Understanding the relationship between severe obesity, substantial weight loss, and lower-extremity alignment may be clinically important because mechanical loading is closely related…

A promising-looking record is not the same as confirmed eligibility. The study team must review the full criteria and current recruitment status.

Basic eligibility

Age18 Years to Not listed

SexAll

Healthy volunteersNot accepted

ConditionObese, Limb Deformities, Arthritis

Full registry criteria

Inclusion Criteria: * Adults aged 18 years or older. * Patients with morbid obesity who are scheduled to undergo bariatric surgery according to routine clinical indications. * Ability to stand independently for standardized weight-bearing lower-extremity radiographic assessment. * Availability of an appropriate preoperative standing full-length lower-extremity radiograph allowing assessment of the hip, knee, and ankle centers. * Planned postoperative clinical and radiographic follow-up at approximately 3, 6, and 12 months. * Ability and willingness to participate in the prospective follow-up protocol. Exclusion Criteria: * Previous lower-extremity corrective osteotomy, joint arthroplasty, or major reconstructive surgery that substantially alters mechanical alignment. * Previous fracture malunion or major skeletal deformity involving the pelvis, femur, tibia, knee, or ankle that prevents representative mechanical-axis assessment. * Neurological or neuromuscular disorders substantially affecting standing lower-extremity alignment. * Inability to obtain technically adequate standardized standing full-length lower-extremity radiographs. * Pregnancy at a time when radiographic assessment would otherwise be required. * Major lower-extremity trauma or surgery occurring during follow-up that may independently alter mechanical alignment. * Incomplete or unavailable radiographic data required for longitudinal analysis.

Treatments and study arms

Obese.

Other

Participants will undergo bariatric surgery as part of routine clinical care according to established clinical indications. The type of bariatric procedure will not be assigned or modified by the study. Participants will be prospectively followed, and lower-extremity alignment and mechanical-axis parameters will be evaluated using standing full-length lower-extremity radiographs before surgery and at approximately 3, 6, and 12 months after surgery. The study will assess longitudinal changes in hip-knee-ankle alignment and related femoral, tibial, and knee joint-line parameters during postoperative weight loss.

Primary outcomes

Change From Baseline in Hip-Knee-Ankle (HKA) AngleBaseline (preoperative), and 3, 6, and 12 months after bariatric surgery

The Hip-Knee-Ankle (HKA) angle will be measured in degrees on standing full-length lower-extremity radiographs using the mechanical axes defined by the centers of the femoral head, knee, and ankle. An HKA angle of 0° represents neutral mechanical alignment. Changes in HKA angle from the preoperative baseline will be evaluated at each postoperative follow-up to determine longitudinal changes in coronal lower-extremity alignment.

Study locations

1 locations were listed when this page was built. The first 40 are shown.

Department of Orthopaedic Surgery and Traumatology, Marmara University, Pendik Training and Research Hospital, İstanbul, Turkey🌐 Istanbul, Pendik, Turkey (Türkiye)

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